Extreme weather events are now on the rise worldwide and are more likely to happen in the future (Easterling et al., 2010). These climate change/variability events are predicted to be characterized by extreme droughts and very wet periods due to flood events. The number of areas that are affected by extreme drought and excessive rains are increasing. Since most livestock productive activity in Africa takes place in fairly confined communal areas, which are often vulnerable to drought and heavy rains, the potential losses due to such disasters have been quite significant (Easterling et al., 2010). The combination of generally increasing temperatures and shifting rainfall patterns will clearly have impacts on grazing land management and livestock production. Feed is predicted to remain a critical constraint on livestock production in the tropics and crop productivity is a useful proxy for feed availability in most regions (IPCC, 2007).
In Africa in general, as in many other parts of the continent, the probability of occurrence of extreme events is predicted to increase in the year-to-year variation in rainfall (IPCC, 2007). It is further explained that the vulnerability of a socio-economic and environmental system to climate change is conceptualised as a function of a system’s exposure to climate change effects and its adaptive capacity or resilience to deal with those effects. There is now a general consensus on the reality of climate change (Stern, 2006). with scientific evidence of its anthropogenic drive getting stronger (Stern, 2006). Climate change resilience, according to Adger et al. (2013), is the adjustment of a system to moderate the impacts of climate change, to take advantage of new opportunities or to cope with the consequences. According to this author, an understanding of the connection between climate on the one hand and livestock grazing management on the other is of great importance if economic growth is to be sustained in developing countries.
Climate change vulnerability is defined as “the degree to which a system is susceptible and unable to cope with adverse effects of climate change, including climate variability and extremes. Vulnerability is a function of the character, magnitude, and rate of climate change and variation to which a
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system is exposed, its sensitivity, and its adaptive capacity” (IPCC, 2007). By understanding the components of climate change vulnerability for a given resource of concern, resource managers and decision makers are better positioned to evaluate alternative actions to respond to climate change, even in the face of considerable uncertainty. These alternative actions are known as climate change adaptation strategies (Nichols et al., 2011).
The earth’s changing climate is forcing reconsideration of strategies for conserving natural resources. Managers need to understand where and when the resources they manage might be vulnerable to climate change. They also need a better understanding of the factors that contribute to that vulnerability.
This knowledge is essential to determine which management actions will be suitable over the coming decades (Young et al., 2013).
Climate change represents a globally pervasive stress on natural ecosystems.
Temperature and precipitation regimes drive ecosystem productivity and natural dynamics, such as the rate of plant growth, the frequency of natural wildfire, and the seasonal flow of streams. Paleoecology has shown that past episodes of climate change triggered ecosystem change at regional and local levels with varying speed and intensity (Wells, 2003; Betencourt et al., 2010). As the current rate of global change increases, society can expect profound shifts in key ecological processes to cascade through natural systems, resulting in altered productivity, changes to species composition, local extinctions, and many instances of ecological degradation or collapse (IPCC, 2007).
As Fagre et al., (2009) pointedout, we are scarcely prepared for these changes.
While the modern scientific study of ecosystems dates back over a century, we do not sufficiently understand the many linkages between key climate variables and ecosystem dynamics across diverse landscapes; nor do we fully understand the effects of other stressors, such as those tied to land use, that have already reduced the resiliency of many natural ecosystems. One certain conclusion that we can draw from our experience is that ecosystems will not simply ‘move’ as climate changes, but will instead transform in unprecedented ways because of the controlling link between climate and many ecosystem processes including the individualistic responses of species (Finch, 2012).
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Climate change adaptation includes actions that enable species, systems and human communities to better cope with or adjust to changing conditions. These strategies may take a number of forms. Some have categorised strategies into three areas, including resistance, resilience, and facilitated transformation ((Milly et al., 2012; McLachlin et al., 2007). Same authors also indicated that resistance strategies for adaptation aim to prevent the direct effects of climate change. Frequently cited examples include building sea walls and coastal hardening to prevent the effects of coastal sea-level rise (Klein and Nicholls, 1999). Preventive measures to head off effects of invasive species, or uncharacteristic landscape-scale fires could also fall into this category.
As McLachlin et al. (2007) describe resilience strategies aim to secure the capacity to cope with the effects of climate change by ensuring that critical ecological processes as currently understood are restored to a high level of function or integrity. For example, by securing large and interconnected natural landscapes, patterns of species dispersal and migration are secured to protect food-web dynamics. Facilitated transformation strategies anticipate the nature of climate-change induced transitions and, working with these anticipated trends, include actions that facilitate transitions that are congruent with future climate conditions, while minimising ecological disruption (Milly et al., 2012).
Somewhat radical expressions of these strategies might include assisted migration of sensitive community segments from current habitats to locations where changing climates might provide new habitats into the future (McLachlin et al., 2007). Some have characterised these resistance and resilience strategies as ‘retrospective’ because they emphasise utilisation of knowledge about historical or current ecological pattern and processes, i.e. protection and restoration of natural conditions as they are currently understood. Facilitated transformation is therefore a ‘prospective’ set of strategies in that they are based on the hypothesis of future conditions (Magnuss et al., 2011). On top of this, there is a critical temporal dimension also to adaptation strategies.
Conservation decisions are made often within the existing policy and law institutional constraints (McLachlin et al., 2007), while traditional natural resource management has been utilising knowledge of past and current
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conditions to inform today’s management actions and forecast future conditions (Comer et al., 2012).
According to Comer et al. (2012):
“This forecasting must strive to determine the nature and magnitude of change likely to occur, and translate that knowledge to current decision-making. It is no longer sufficient to assess how are we doing?’ and then decide what actions should be prioritized for the upcoming 15 year management plan. One must now ask ‘where are we going, and by when?’ and then translate that knowledge back into actions to take in the near-term, or medium-term, or those to monitor and anticipate taking over multiple planning horizons. Considerable new science and policy will be required to support this new type of natural resource decision making”.
Coping with uncertainty is another dimension for adaptation. Uncertainty is inherent in climate change vulnerability and adaptation planning. It is important to clarify areas of uncertainty so that efforts by users to appropriately interpret and invest in new knowledge to reduce uncertainty can be effectively focused (Risbey and Kandlikar, 2012; Swart et al., 2009).